Back in the 90s, AOL, then known as America Online, sent out what seemed to be billions of free promotional CDs to practically every person in the country. Urban legend suggests that an astonishing ten percent of the Earth’s mineral resources could be reclaimed if those landfilled CDs were recycled. Alright, we’re making up that statistic, but still: AOL undeniably sent out a lot of CDs.

Here’s the question, though: how much did AOL pay to bombard every citizen in America with dozens of plastic discs? The answer, according to one-time AOL CEO Steve Case, is a bigger number than we would have expected: “about $35 per user.”

According to an answer Case posted on popular Q&A site Quora:

“I don’t remember the total spending but do recall in the early 1990s our target was to spend 10% of lifetime revenue to get a new subscriber. At that time I believe the average subscriber life was about 25 months and revenue was about $350 so we spent about $35 to acquire [subscribers].”

That’s not to say each disc cost $35, just that the complete cost of all discs, plus postage and marketing, was $35 per subscriber. The number shrinks substantially once you consider all of the people who didn’t describe.

Make no mistake, though. This strategy paid off. According to Case, “ When [AOL] went public in 1992 we had less than 200,000 subscribers; a decade later the number was in the 25 million range.”